package QueueDemo;

public class MyCircleQueue {
    public int[] elem;
    public int useSize;
    public int front;
    public int rear;
    public MyCircleQueue(int k) {
        elem = new int[k];
    }

    public boolean enQueue(int value) {
        if(isFull()){
            return false;
        }
        elem[rear] = value;
        rear = (rear+1) % elem.length;
        useSize++;
        return true;
    }

    public boolean deQueue() {
        if(isEmpty()){
            return false;
        }
        front = (front + 1) % elem.length;
        useSize--;
        return true;
    }

    public int Front() {
        if(isEmpty()){
            return -1;
        }
        return elem[front];
    }

    public int Rear() {
        if(isEmpty()){
            return -1;
        }
        int index = rear == 0 ? elem.length-1 : rear-1;
        return elem[index];
    }

    public boolean isEmpty() {
        return useSize == 0;
    }

    public boolean isFull() {
        return useSize == elem.length;
    }

}
